Plot showing the variation of L_median (in erg s⁻¹) with z along with observed Swift data and simulated data. The plots in panel a correspond to F_th = 2 × 10⁻⁸ erg cm⁻² s⁻¹. The plots in panel b correspond to F_th = 1 × 10⁻⁷ erg cm⁻² s⁻¹. The values of the parameters are marked on the plots. The orange dots represent the simulated data. The other, larger dots correspond to the observed data for long, short, and ultralong GRBs (Goldstein et al. 2017; Cano et al. 2017; Michałowski et al. 2018; Gehrels et al. 2006; D’Avanzo et al. 2014; Demianski et al. 2017). The terms monotonic, flat, and unavailable correspond to the nature of afterglow data for the corresponding GRB. The curve marked threshold represents the threshold value (for the rest of the plots in this paper) of L at a given z. For comparison, we also plot the curve (green and brown) corresponding to the ILF given by a broken power law.